Sustainability Math A Quantitative Literacy and Mathematics Resource for Instructors

Kevin Drum provides an overview and update of the hypothesis in his detailed post An Updated Lead-Crime Roundup for 2018. In short,

The lead-crime hypothesis is pretty simple: lead poisoning degrades the development of childhood brains in ways that increase aggression, reduce impulse control, and impair the executive functions that allow people to understand the consequences of their actions. Because of this, infants who are exposed to high levels of lead are more likely to commit violent crimes later in life.

He notes further down in the article that

It’s important to emphasize that the lead-crime hypothesis doesn’t claim that lead is solely responsible for crime. It primarily explains only one thing: the huge rise in crime of the 70s and 80s and the equally huge—and completely unexpected—decline in crime of the 90s and aughts. The lead-crime hypothesis is the answer to the question mark in the stylized chart below:

The post has useful graphs for QL based courses, provides an overview of the hypothesis, and the Statistics Projects section of this blog has lead-crime data for projects.

The PRB (Population Reference Bureau) post, Declines in Adult Death Rates Lag in the U.S. South, answers the question with interactive graphs.

Adult death rates in many southern states are 30 percent or 40 percent higher than in states with the lowest death rates. The growing geographic disparity means that adults (ages 55+) in the worst-off southern states can expect to die three to four years earlier, on average, than their counterparts in states with the lowest death rates.

The graphs show death rates by state and state rankings for both females and males, from 1980 to 2015.  There is a clear trend.

In 2015, all of the states with the highest female death rates (ages 55+) were located in the South. In 1980, by comparison, the five states with the highest female death rates included Louisiana, New Jersey, New York, Ohio, and Pennsylvania.

The set of graphs are perfect for a QL course. The data, cited in the post, is from the CDC which could make for a regression based statistics project.

The Climate Central post, Small Change in Average -Big Change in Extremes, summarizes the idea well with the graph. As the mean shifts to the right, there is a significant increase in the chance of extreme temperature. The animated gif on the site is perfect in expressing the idea.

That’s what we are seeing across much of the country. Average summer temperature have risen a few degrees across the West and Southern Plains, leading to more days above 100°F in Austin, Dallas and El Paso all the way up to Oklahoma City, Salt Lake City, and Boise.  It’s worth noting that this trend has been recorded across the entire Northern Hemisphere, as shown in this WXshift animation.

You should check out the WXshift page they link to. This material is perfect for a stats course. It is also worth pointing out that the pictures here assumes the standard deviation stays the same, but there is evidence that it may be increasing. The effect is a flatter more stretched out density, with even greeter likelihood of extremes.

Kevin Drum has the answer with his post Black Incomes Have Fallen Further Behind Whites for the Entire 21st Century.

Black men have made essentially no progress in the past four decades, while black women have fallen considerably further behind. Since 2000, both both men and women have fallen further behind their white counterparts.

There are two other graphs and he notes:

Black households made income and wealth gains up through about 2000, but since then have gone backwards. Any way you look at this, the gap between blacks and whites has gotten worse throughout the entire 21st century. Anyone who doesn’t understand why the African-American community has seemingly become more despairing of racial progress lately should take a look at this.

The data for the graph here comes from FRED. If you haven’t used FRED it is an excellent resource.  To get you started with FRED by comparing black vs white earnings (not separated by gender)  go here and then click on edit graph. Add the series LEU0252883700Q under customize data. Then under formula type a/b.  You should get the graph below. You can then download the data and graph.

The Chicago Booth post, Never mind the 1 percent Let’s talk about the 0.01 percent, provides an insightful summary of income distribution at the top.

Mankiw noted that the 1 percent’s share of total income, excluding capital gains, rose from about 8 percent in 1973 to 17 percent in 2010, the latest figures available at the time. “Even more striking is the share earned by the top 0.01 percent. . . . This group’s share of total income rose from 0.5 percent in 1973 to 3.3 percent in 2010. These numbers are not easily ignored. Indeed, they in no small part motivated the Occupy movement, and they have led to calls from policymakers on the left to make the tax code more progressive.”

There is detailed exposition on who makes up the top and how they got there. For instance,

Technology, from the internet to media such as ESPN and Bloomberg terminals, has given elite athletes, entertainers, entrepreneurs, and financiers the ability to profit on a much larger, global scale, making the fruits of their labor more valuable than what previous superstars, such as, say, Pelé or Babe Ruth, brought in. Ruth’s peak salary of $80,000 would be worth about $1.1 million in 2016 dollars, around one-thirtieth of the $33 million the highest-paid Major League Baseball player, pitcher Clayton Kershaw of the Los Angeles Dodgers, made in salary alone in 2016.

And hedge-fund managers make multiples more than top athletes and entertainers. James Simons of Renaissance Technologies and Ray Dalio of Bridgewater Associates each made more than $1 billion in 2016, even though, as Institutional Investor’s Alpha reported, the top-25 hedge-fund earners took in the least as a group since 2005, largely because of the industry’s overall poor investment performance.

This is an excellent article about income and how it is distributed, with a number of graphs suitable for QL based courses.

According to NOAA’s article, Assessing the U.S. Climate in 2017, it was the third hottest year on record for the U.S. It also wasn’t an El Nino year. In summary,

This was the third warmest year since record keeping began in 1895, behind 2012 (55.3°F) and 2016 (54.9°F), and the 21st consecutive warmer-than-average year for the U.S. (1997 through 2017). The five warmest years on record for the contiguous U.S. have all occurred since 2006.

For the third consecutive year, every state across the contiguous U.S. and Alaska had an above-average annual temperature. Despite cold seasons in various regions throughout the year, above-average temperatures, often record breaking, during other parts of the year more than offset any seasonal cool conditions.

The article has other useful graphs and information, including a summary for December.  Related data is linked to their Climatological Rankings page.

According to the 3rd chart of EPI’s Top Charts of 2017, U.S. minimum wage would be $19.33 per hour if it grew at the same rate as productivity.  If it simply grew at the rate of average workers it would be $11.62 per hour.

The expectation that the minimum wage rise in step with broader trends in the economy would not have been unreasonable for previous generations—that was the trend throughout the 1950s and 1960s. Today’s minimum wage workers have been harmed both by the failure to raise the minimum wage in step with pay for typical workers and by the huge and growing gap between these nonsupervisory wages and economy-wide productivity. The Raise the Wage Act of 2017 would raise the federal minimum wage to $15 by 2024. Such a raise would certainly bring the pay of minimum wage workers closer to providing a decent quality of life, even though it would still fall short of what the economy could have delivered for low-wage workers over the past 50 years.

All twelve of EPI’s Top Charts of 2017 include data and you can download the chart.

The EPI provides evidence for yes in the 6th of their top charts of 2017, The racial wealth gap is the clearest legacy of past discrimination in housing markets. Their chart shows the differences for mean and median household wealth for black and white households. They key is housing:

Besides facing discrimination in employment and wages, black families historically have been shut out of the most important wealth-building market: housing. Overall, home equity makes up about two-thirds of all wealth for the typical household. In short, for median families, the racial wealth gap is overwhelmingly a housing wealth gap. And this housing wealth gap is no accident; it is the outcome of intentional policies at all levels of government, in particular housing policies that prevented blacks from acquiring land, created redlining and restrictive covenants, and encouraged lending discrimination. These policies created and reinforced the racial wealth gap we are still struggling to address.

You can download the data and graph for all of EPI’s top charts of 2017.

Happy New Year and thank you to all of you who have stopped by Sustainability Math this past year. If people didn’t visit the blog, then I’d stop writing.  Posts will begin again next week. In the meantime, consider following Sustainability Math on Twitter and Facebook. Also, please let friends and colleagues know about the blog.

The New York Times article, Beavers Emerge as Agents of Arctic Destruction, explains:

… as climate change warms the Arctic and thaws the permafrost, the growing season extends. What was once tundra gives way to brush.

This may allow beavers to move north.

But in the tundra, the vast treeless region in the Far North, beaver behavior creates new water channels that can thaw the permanently frozen ground, or permafrost.

What remains is a pitted landscape, with boggy depressions, that directs warmer water onto the permafrost, leading to further thawing. As permafrost thaws it releases carbon dioxide and methane, which in turn contributes to global warming and helps increase the speed that the Arctic, which is already warming faster than the rest of the planet, defrosts.

This is an interesting article with satellite photos showing how beavers have changed the landscape.